In this book, I assume that you have one of Cisco’s 800 Series or SOHO Series broadband routers on hand. You can use other Cisco models, but an 800 series running Cisco Internetworking Operating System (IOS) version 12.4 will be referenced in my examples. The 800 series routers are great, low-cost devices that have all the functionality small businesses need, with the added benefits that Cisco’s IOS has to offer.